Hot-air furnace



(No Model.)

L. J. MUELLER,

HOT AIR FURNACE.

No. 866,193. Patented June 21, 1887.

on Zine ac ac UNITED STATES ATENT OFFICE.

LOUIS JOHN MUELLER, OF MILXVAUKEE, \VISOONSIN.

HOT-=AlR FURNACE.

SPECIFICATION forming part of Letters Patent No. 365,193, dated June 21,1887.

Application filed May 26, 1886. Serial No. 203,315.

To all whom it may concern.-

Be it known that I, Louis J OHN MUELLER, of Milwaukee, in the county ofMilwaukee and State of IVisconsin, have invented certain Improvements inHot-Air Furnaces, of which the following is a specification.

My invention relates to the formation of the radiating-surfaces and thepassages through which the products of combustion are directed; and itconsists in the peculiar constructions hereinafter described andclaimed,havi ng as an object an increased radiating-surface and athorough circulation of the heated parts.

In the accompanying drawings,Figure 1 represents a vertical centralcross-section of the improved furnace from front to rear, on the line a:00 of Fig. 2. Fig. 2 is a top plan view of the same.

Referring to the drawings, A represents the base or ash-pit of thefurnace; B, the fire-pot; G, a dome or chamber rising centrally abovethe fire-pot and combustion-chamber in position to receive the ascendinggases and products of combustion.

D is an inner chamber or radiator encircling the upperend of the domeand communicating with the base of the dome by a series of uprightfiues, a.

E is a second annular chamber or radiator encircling the first andcommunicating there with at the front and rear by the horizontal tubes(1 and c, and also communicating at its under side by vertical flucs fwith the outer portion of the dome. It will be observed that the base ofthe dome O is expanded or curved outward to receive the vertical fines aand f.

It is to be noted as an important feature of my construction that thelowerends or months of the flues a are at a considerably higher levelthan the mouths of the fines f, by reason of which fact and of the factthat theyare nearer the center of the furnace the heated products andgases rising into the dome O are directed mainly through the fiues a intheir outward passage. In practice it is found that the products have astrong tendency to ascend centrally into the dome O, and descend thencealong its inner surface to the lower mouths of the flues a and f. Suchof the products as fail to enter the fines a continue their downward andoutward course until they enter the fluesf. If desired, a valve ordamper, b, may

(No model.)

be placed in the rear pipe, d. \Vhen this chamber is closed, theproducts ascending through the fines a into the radiator D will becompelled to pass outward through the pipe 0, and thence rearwardthrough the radiator E, in order to reach the smoke-flue M, which opensfrom the rear side of radiator E.

I am aware that radiating-chambers of different forms have beenconnected with each other by pipes and fines variously arranged; but Ibelieve myself to be the first to combine with the central dome the tworadiators D and E and their vertical fines opening into the top of thefurnace at different heights.

G, II, I, and K represent, respectively, the grate,its rocking-lever,anotched bar to permit the removal of the lever in one position only; andk, a stud on the journal of the grate. These devices form no part of thepresent invention.

Having thus described my invention, what I claim is- 1. In a hot-airfurnace, the dome O, located immediately over the fire-pot to receivethe ascending products of combustion, in combination with the twoannular radiators D and E, the fiues f, leading from the outer radiatorinto the lower end of the dome, and the fines a, leading from the innerradiator into the dome, their mouths being at a higher level than themouths of fiuesf, as shown, whereby the products descending in the outerpart of the dome are divided and delivered in part to each radiator.

2. In a hot-air furnace, the dome 0, located centrally over thefire-chamber,in combination with the annular radiator D and its flues a,entering the base of the dome, the radiator E and its fines f, enteringthe base of the dome at a lower level than the first-named fines, andthe connecting-pipes c and (7,.

3. In combination with the dome O, the ra diators D and E, the verticalfines a andf, the connecting-pipes c d, and a valve, 1), located asdescribed.

In testimony whereof I hereunto set my hand, this 8th day of March,1886, in the pres ence of two attesting witnesses.

LOUIS JOHN MUELLER.

Witnesses:

WILLIAM Manrrnns, HENRY O. Ronrrrnrsnnnonn.

